let _ = require('underscore')
let $ = require('jquery')
let lodash =require('lodash')
console.log($)
let arr = [3, 2, 4, 1, 5]
//找第一个偶数
let arr1 = _.find(arr, (item) => {
  return item % 2 === 0
})
console.log(arr1)
//找所有给偶数
let arr2 = _.filter(arr, item => item % 2 === 0)
console.log(arr2)
//找第一个偶数的index
let index = lodash.findIndex(arr,(item)=>{
    
})
